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Python Infinity - Any caveats?
...involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**2
4294967296.0
>>> _**2
1.84467440737...
Why does running the Flask dev server run itself twice?
...g is the library that supplies Flask with the development server when you call app.run().
See the restart_with_reloader() function code; your script is run again with subprocess.call().
If you set use_reloader to False you'll see the behaviour go away, but then you also lose the reloading function...
AttributeError: 'module' object has no attribute 'tests'
...
I finally figured it out working on another problem. The problem was that my test couldn't find an import.
It looks like you get the above error if your test fails to import. This makes sense because the test suite can't import ...
undefined reference to boost::system::system_category() when compiling
...raries. I have the 1.46-dev Boost libraries from the Ubuntu Repository installed, but I get an error when compiling the program.
...
How to get the error message from the error code returned by GetLastError()?
After a Windows API call, how can I get the last error message in a textual form?
11 Answers
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Add custom messages in assert?
...rk; they’re compile-time constants and their use in this context is trivially optimized away. There is no runtime cost.
– zneak
Aug 9 '19 at 8:46
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Why can't (or doesn't) the compiler optimize a predictable addition loop into a multiplication?
...
The compiler can't generally transform
for (int c = 0; c < arraySize; ++c)
if (data[c] >= 128)
for (int i = 0; i < 100000; ++i)
sum += data[c];
into
for (int c = 0; c < arraySize; ++c)
if (data[c] >= 12...
Nested classes' scope?
...e will use that object the next time it is executed.)
If you instead want all Inner objects to have a reference to an Outer because outer_var is really an instance attribute:
class Outer(object):
def __init__(self):
self.outer_var = 1
def get_inner(self):
return self.Inner...
What is the difference between char s[] and char *s?
...puts the literal string in read-only memory and copies the string to newly allocated memory on the stack. Thus making
s[0] = 'J';
legal.
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Cannot kill Python script with Ctrl-C
...you can't do anything with it after it exits. The process will finish when all non-daemon threads have finished; parent-child relationships don't come into that.
– Thomas K
Dec 6 '13 at 22:22
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